Lilyanthe

So all the previous methods I knew for making gems is now long gone, or maybe I've forgotten how? I'm more or less almost done with the campaign. I'm in the middle of act 10 and I've received some hongmoon pentagonal gems. Since I'm just now coming back I can't solo some instances that drop a hongmoon gem box, but as we know drop rates are abysmal. Tl:dr where do I get more hongmoon gems??